1. Field of the Invention
The present invention relates to a desktop book binder for binding loose sheets of paper into a book and wherein means are provided for aligning the sheets of paper with binding material which has been formed into an L-shape.
2. Description of the Prior Art
Many techniques have evolved over the past centuries for binding loose sheets of paper into a book. One Such teaching uses tapes coated with hot-melt glue and wrap-around folders having hot-melt glue on the inside of their spine. In this-method, the tape or folder is wrapped around the edges of the bundle of papers to be bound and the glue is heated. The glue adheres to the paper, the binding process being completed when the glue cools.
A major problem with this method is the accurate alignment of the tape with the edges of the paper. Sophisticated solutions capture both the paper and tape which are brought into alignment using sensors and automated precision mechanisms. This solution is expensive. Another method that may achieves alignment is by preforming the tape""s cross section into a U-shape. The paper is placed inside the U and the combination is heated for binding. Because the width of the U is fixed, many different tape sizes must be stocked.
With respect to the folder binding, paper is dropped into the folder and the combination then heated to melt the glue to complete the binding. Like the preformed U-shaped tapes, the widths of the folders are fixed so the user must stock many sizes, thus increasing costs since folders are expensive.
Examples of various binding techniques are disclosed in the following U.S. patents. U.S. Pat. No. 4,129,471 to Rome discloses a system wherein a cover folder has an adhesive material in the backbone area; U.S. Pat. No. 3,717,366 to Decker discloses a system wherein an adhesive material is applied to the inside of a folded book cover and a device to fold the book cover; U.S. Pat. No. 3,321,786, to Bollick, Jr. discloses a book binding apparatus wherein a platform is provided for stacking the paper to be bound, a rise element for clamping the stacked edge of paper together, a device for applying an adhesive to the stacked edge of paper and means for heating the adhesive material for a predetermined period of time; U.S. Pat. No. 4,496,617 to Parker discloses an improved binding strip for binding a stack of sheets together; and U.S. Pat. No. 3,757,736 to Anderson discloses a bookbinder apparatus wherein pages are clamped in a carriage and edges aligned by a vibrator in a first angular position, the carriage rotated for a preheating stage, hot-melt glue applied to the edges and the bound papers then moved to a cooling position.
Printing on thermal binding tapes is also difficult both because the tapes are difficult to align with a printer and because they are not compatible with printer feeding mechanisms. After binding, specialized spine printers are available but they typically print only on the spine and print only in black and white, and are limited to the dimensions of the area they can cover. In addition, when only a few books are thermally bound at a time, professional spine printing is prohibitively expensive. When printing books on demand or in an office environment, the number of books is usually limited. In these cases, after thermal binding, the spine is left blank. This is both annoying and inconvenient. What is thus desired is to provide a binding apparatus which is simple and inexpensive wherein both sheets and folders are easily bound in the apparatus and wherein the binding tapes can be easily printed simply and economically before the binding tapes are inserted into the apparatus even if only a few books are bound at a time. In addition, it is desirable to provide an arrangement wherein the binder tape is formed as part of the binding covers prior to insertion into the binder apparatus, thus avoiding the possibility that a user""s fingers do not have to be inserted into the cavity. In addition, it is desirable to provide a cover which can be printed easily on a conventional printer but then joined with the adhesive layer to form a bound assembly.
The present invention provides a simplified desktop book binder method and apparatus wherein the sheets to be bound are accurately aligned by the binder tape itself and wherein the preformed binder tape also enables various thickness books to be bound. In particular, conventional binder tapes are formed into an L-shape. Alignment is achieved since the inside corner of the L and the edge of the bundle of sheets of paper fit together exactly. The long leg of the L-shape is oriented horizontally.
The tape is dropped into a correspondingly shaped slot in the binder apparatus and the paper bundle is placed on top of the tape, the edge of the bundle being automatically aligned against the corner of the tape. The free end of the long leg of the L-shape tape can be wrapped tightly around the paper bundle, thus handling variations in bundle thickness.
In an alternative arrangement, instead of binding a bundle of papers between covers, a form whose shape resembles that of a slat is substituted for the bundle of paper. The form is covered with Teflon tape. Since the glue will not adhere to the Teflon, the form may be removed, after binding. This leaves the covers and binding tape with glue inside the spine. Thus, the user may make his/her own folders, only the number and width needed at the moment required to be made. The covers used to make the folders then can be printed on using conventional printers before the sheet binding procedure is initiated. Thus, flexibility is enhanced and cost is greatly reduced as well.
Prior to bending into the desired preformed L-shape, the tapes are flat. In another option, they are assembled side-by-side to form a sheet, the sheet being held together by a backing of release paper. The sheet can be passed through an ordinary desktop printer wherein text, labels, title, logos, images, bar-codes, etc. can be printed in color or black and white on the sheet of tapes. The tapes, once printed, can then be peeled off of the sheet. The L-shaped bend is made manually along a pre-scored line in the tape, the preprinted tape now being ready for binding. Still another option is to provide a sheet of release paper with only a narrow strip of release adhesive. A single tape can be flattened manually and applied, glue layer down, to the narrow release adhesive strip. The combination can now be passed through a printer. By this method, single tapes may be printed upon by an ordinary desk top printer. After printing the tape is striped off the sheet of release paper. The tape is manually rebent into the L-shape and is used for binding. The sheet of paper with the strip of release adhesive may be reused several times until the release adhesive strip will no longer adhere to a tape. The assembly of one or more tapes into sheets enables preprinting of the tapes on the user""s own printer.
The tape with the L-shaped bend is inserted into a slot formed in the top of the binder apparatus. The corner of the bend in the tape is aligned with the bottom corner or edge of the slot. The paper bundle is then inserted on top of the tape. The user then depresses a lever on one end of the binder apparatus to initiate the process. The binding process consists of clamping the paper bundle and binding tape together in proper alignment, wrapping the binding material around the paper bundle, melting the glue so that it adheres to the edges of the sheets of paper in the bundle, and allowing the assembled document to cool. After a cooling period, the operator depresses a lever on the other end of the binder apparatus to release the bound document and reset the binder apparatus for the binding sequence.
The unique L-shaped tape enables easy, accurate alignment with the paper bundle, thereby simplifying the binder apparatus design. The binder apparatus, as will be explained in more detail hereinafter, includes a movable platen, clamping stop, and bender a configuration which assures tight accurate folding of the tape around the paper bundle.
The heaters used to melt the tape glue have a very small thermal mass, direct heating of the tape or folder thus eliminating any warm-up requirement. The heaters have a Teflon or silicone surface treatment which prevents preprinted tapes from transferring ink to the heater during the binding operation. The heaters include a thermal insulator enabling a fast glue-heating cycle balanced with a rapid cool-down requirement. Preheating of the binding tape assures gentle handling of fragile documents during tape bending. Controlled heating of the binding tape allows glue of a substantially uniform thickness to be applied to the tape in contradistinction to the non-uniform glue thickness of many prior art binder tapes, reducing the cost of the binding tapes and thus of the binding process.
The tapes used in the present invention can be assembled into sheets enabling preprinting of the tapes on the user""s own printer, selection of appropriate tape widths when assembled in sheet form allowing the operator to use standard label making software and avoid unprintable areas along the edges of most printers.
In alternative embodiments, the adhesive member is formed as part of the book cover itself to avoid a user inserting his/her fingers into the binder cavity to insert the binding tape. In another embodiment, a carrier sheet having a L-shaped adhesive strip is positioned against a front cover and used to bind an assembly further comprising sheets and a back cover, thus allowing the front flat cover sheet to be printed without the adhesive (glue) layer formed thereon.
A removable Teflon coated form may be used to replace the paper during binding, thus enabling the user to make and customize binding folders for later use.
The present invention thus provides a simple binder apparatus which provides a number of user desired features at a relatively inexpensive cost.